Chat New car in the CHB household!

There's 2 versions of the i3 Dave. An all electric version or the range extender (Rex). The Rex is clever in that it's actually a bmw motorbike engine so it's less than 1 litre (0.7cc) however The petrol is used to drive the electric motor which powers the wheels.
 
So does that mean that when you get low on electric you can "switch over " onto the petrol engine to recharge the battery when you are travelling or is the petrol engine running all the time to reduce the electric drain ?.
 
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Got it in one Dave, the Rex engine is off and only kicks when you want it to or when you're about to run out of juice. That's my understanding of it anyway
 
That's exactly right Hass. So for most of my driving (60 mile daily commute) the REX generator just sits there and does nothing.
The batteries on mine are around 18kWh, so at 13p a kW from EDF that's £2.34 for a full charge that gives approx. 90 miles petrol free driving.

The REX generator will throw out an estimated 19kW and is has a tiny fuel tank of about 7 litres.

My average driving seems to be approx. 4 miles per kW at the moment, but at motorway speeds the i3 will do less than this.

In most driving the REX will generate enough power to keep the batteries topped up with capacity to spare.
At motorway speeds the REX cannot generate power as quickly as the motor needs, so you might be generating 18kW from the REX but needing 23kW to drive at 70mph (made that last number up, but it is more than 18!). So the battery will gradually drain by 5kW per hour unless you get stuck in traffic or slow down to non-motorways speeds.
In reality, I think that unless you wanted to do 300-350 miles in one stretch with no charging then the REX would keep up enough. I did 220 miles this way and I chose to use the last 40 miles of battery to get me home. I could have done another 100 miles at 70mph and used the REX to slow down battery use.
Clever system and works well.
 
I've got some tired 17" wheels with tyres if you like for a modest cost - I'm open to discussion. They will definitely need a refurb...
 
Hi Simon,

Please post these wheels in the "for sale" section of the "market place" with a fixed price so they don,t get lost in this thread.

Many thanks

Dave:)
 
Think of the rex as being a fuel driven generator that can charge the battery when it is flat or nearly flat.

Basically you could buy a petrol generator and it would do the same thing (although the technology on the REX is more complicated).


So it is only electrically connected to the batteries and does nothing for the driven wheels or performance etc.

Steve B
 
I hope they work on extending the range to at least 1000 km on one charging, that would do for me. Until then, I'm filling the tank


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Darko, thankfully in the crowded little island I call home you are never more than 5 miles from a petrol station (apart from the very north of beautiful Scotland, but we have the XC90 for those trips!).
I have just ordered a set of 19" turbine rims with Bridgstone winter tyres, when I pick them up I will post pictures as the wheels are HUGE!
 
Hi Dave

think of it as exactly the same car but with a fuel driven generator that is used to charge the batteries as you drive.

Basically that is it (but with a little "electrickery". No connection between the fuel driven engine and the wheels/power, but very useful if you are running low on charge in the middle of nowhere.

Steve B
 
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chb said:
Darko, thankfully in the crowded little island I call home you are never more than 5 miles from a petrol station (apart from the very north of beautiful Scotland, but we have the XC90 for those trips!).
I have just ordered a set of 19" turbine rims with Bridgstone winter tyres, when I pick them up I will post pictures as the wheels are HUGE!
Click to expand...

HUGE is best :)


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